G Body 12 bolt swap

[killastreetbu]

What do I need to do to get a 12 bolt in a gbody

 

[454RAT]

The correct control arms. Check out baseline suspesnsions. Your "normal' off the shelf control arms will not correct the geometry that the 12 bolt housing and other housings have.

 

[bowtie81]

Which yr of 12 bolt are you going with? You will need different b/s for rims, 12 bolt swap control arms, proper u-joint to match the rear to your d/s.
My 12 bolt is out of a 67 chevelle, I use 5.5 b/s on a 15x8 rim, iceman 12 bolt swap control arms and it all fits great.

 

[killastreetbu]

I'm using a 12 bolt out of a 70 chevelle. I already have lower CA's & ARB.

 

[bowtie81]

You'll need more of a b/s with that rear, they are a bit wider than the earlier ones. Probably around 6.5 b/s

 

[SSedan64]

68-72 A-body rear is 1" wider than 65-67 .50" / 1/2" per side.
65-67 = 60" WMS to WMS
68-72 = 61" """""" "" """""""
78-88 G-body = 58"

WMS = Wheel Mounting Surface or Drum to Drum.

 

[killastreetbu]

Do I have to move the spring perch & lower control arm brackets.

 

[Grcrygtr44]

I don't think so. I've seen both width rears in g body's and they used the same perches and control arm brackets.

 

[Jayz81ss]

I have a 71 in my Monte. I run 15x8 with a 5.5 backspace. The car came with Southside lowers and had stock uppers. My 60 foots were 1.52 to 1.58. The car was never consistent. The angle of the upper arms caused binding and destroyed the upper bushings.

Now that I have went to more power last fall, I'm in the middle of installing all new rear suspension. As stated above Baseline Suspensions or Trick Chassis sells a kit for the 12 bolt in a G body. I went with Trick Chassis because they have everything I needed and only had to pay shipping from one place. Shipping to Canada is crazy. I ordered the 12 bolt swap kit, Spherical bushings, and an Anti-roll bar.

I recommend using spherical bushings in the uppers no matter who you go with.